French Strings Meeting - Institut Denis Poisson, Tours, June
3-5, 2025
(Click on title to download the slides, if available)
Review talks:
Short talks:
- Khalil Bendriss (L2C): "Mock
modularity of Calabi-Yau threefolds"
- Zhongwu Chen (LPENS): "An Unusual BPS
Equation"
- Camille Eloy (LPENSL): "Charting the Conformal Manifold of
Holographic CFT2s"
- Adrien Fiorucci (CPHT): "Flux-Balance Laws in Flat-Space
Holography" - The main challenges in constructing a
holographic correspondence for asymptotically flat
spacetimes lie in the null nature of the conformal boundary
and the non-conservation of gravitational charges in the
presence of gravitational radiation. In this talk, I shall
demonstrate that there exists a sys- tematic and
mathematically robust approach to understanding and deriving
the associated flux-balance laws from geometric
considerations intrinsically on the boundary. I shall begin
by reviewing key aspects of the geometry at null infinity,
which has been termed conformal Carroll geometry. I shall
emphasise that boundary affine connections possess degrees
of freedom that precisely serve as the sources encoding
radiation from a holographic perspective. I shall conclude
by first deriving flux-balance laws in an effective field
theory frame- work at the boundary, employing novel
techniques that introduce "hyper- momenta" as responses to
fluctuations in the boundary connection, then matching them
with the celebrated BMS flux-balance laws within a
convenient boundary-gauge fixing. Based on arxiv:2505.00077
in collaboration with S. Pekar, P. Marios Petropoulos and M.
Vilatte.
- Romain Gervalle (IDP): "Black holes with electroweak hair"
- When the bosonic sector of the electroweak theory is
minimally coupled to General Relativity, magnetic
Reissner-Nordstrom black holes become unstable below a
critical horizon size. This instability stems from
electroweak condensation, a phenomenon occurring when the
usual Higgs vacuum is subjected to strong magnetic fields.
The condensation breaks the system's spherical symmetry, and
we investigate the hairy black holes arising in this
context, restricting our analysis to the axially symmetric
case. The black hole horizon is surrounded by a condensate
of massive W, Z and Higgs fields. This condensate comprises
two loops of oppositely directed electric currents that
generate a magnetic field with a quadrupolar structure. In
the extremal limit, electroweak symmetry is restored in the
near-horizon region. Remarkably, the extremal hairy black
holes can attain macroscopic sizes, with horizon radii on
the order of a centimeter. Our solutions constitute the
first examples of hairy black holes arising purely within
the framework of the Standard Model and General Relativity.
- Mehmet Gumus (LAPTH): "S-matrix bootstrap and machine
learning"
- Ioannis Tsiares (IPHT) : "On the three-point functions in
timelike N=1 Liouville CFT''
- Philine van Vliet (LPENS):
"Constraints on bulk and defect correlators: the
Maldacena-Wilson line in N = 4 SYM"
- Tom Wetzstein (LPTHE): "The holographic BMS anomalies - "I
will explain the role of anomalies in the extended BMS
symmetry of asymptotically flat four-dimensional gravity. I
will then classify them from both the bulk gravitational
theory and from the boundary field theory perspectives. The
two results agree, provided the associated central charges
are matched. This is the flat space analogue of the
Henningson-Skenderis holographic Weyl anomaly matching in
AdS/CFT.
- Xiang Zhao (IPHT): "Einstein gravity
from a matrix integral"
After dinner talk:
Boris Pioline (LPTHE): "J'ai
l'esprit tout ennuyé", d'après Ronsard, les Odes, 1554